What thickness of PCB copper is too thick for laying out signal components?

[treez]

Hello,
We are laying out an 800W SMPS and wish to use 2oz copper on the PCB....but will this mean that too much heat is required to solder up all the signal components?.....(even if thermal reliefs are used)

Should we put the signal components on a separate "daughter" PCB with half ounce copper?

 

[FvM]

2 oz (70 µ) copper is pretty standard for power electronics PCB. Thermal reliefs are probably unwanted for components carrying high currents. When boards are reflow soldered in production or professional prototyping, they are uniformly heated and copper weight isn't a problem. But it makes rework slightly more difficult and may require preheatimg in some cases.

A problem for signal boards may be caused by the design rules for 70 µ copper, e.g. 250 or 300 µ minimal track width.

 

[jpanhalt]

The etching process may limit the minimum signal trace width: https://www.4pcb.com/pcb-design-specifications/

But, the difference foe 2 oz is slight.

John